LXR uboot/common/cmd

   1/*
   2 * (C) Copyright 2003
   3 * Tait Electronics Limited, Christchurch, New Zealand
   4 *
   5 * SPDX-License-Identifier:     GPL-2.0+
   6 */
   7
   8/*
   9 * This file provides a shell like 'test' function to return
  10 * true/false from an integer or string compare of two memory
  11 * locations or a location and a scalar/literal.
  12 * A few parts were lifted from bash 'test' command
  13 */
  14
  15#include <common.h>
  16#include <config.h>
  17#include <command.h>
  18
  19#define EQ      0
  20#define NE      1
  21#define LT      2
  22#define GT      3
  23#define LE      4
  24#define GE      5
  25
  26struct op_tbl_s {
  27        char    *op;            /* operator string */
  28        int     opcode;         /* internal representation of opcode */
  29};
  30
  31typedef struct op_tbl_s op_tbl_t;
  32
  33static const op_tbl_t op_table [] = {
  34        { "-lt", LT },
  35        { "<"  , LT },
  36        { "-gt", GT },
  37        { ">"  , GT },
  38        { "-eq", EQ },
  39        { "==" , EQ },
  40        { "-ne", NE },
  41        { "!=" , NE },
  42        { "<>" , NE },
  43        { "-ge", GE },
  44        { ">=" , GE },
  45        { "-le", LE },
  46        { "<=" , LE },
  47};
  48
  49static long evalexp(char *s, int w)
  50{
  51        long l = 0;
  52        long *p;
  53
  54        /* if the parameter starts with a * then assume is a pointer to the value we want */
  55        if (s[0] == '*') {
  56                p = (long *)simple_strtoul(&s[1], NULL, 16);
  57                switch (w) {
  58                case 1: return((long)(*(unsigned char *)p));
  59                case 2: return((long)(*(unsigned short *)p));
  60                case 4: return(*p);
  61                }
  62        } else {
  63                l = simple_strtoul(s, NULL, 16);
  64        }
  65
  66        return (l & ((1 << (w * 8)) - 1));
  67}
  68
  69static char * evalstr(char *s)
  70{
  71        /* if the parameter starts with a * then assume a string pointer else its a literal */
  72        if (s[0] == '*') {
  73                return (char *)simple_strtoul(&s[1], NULL, 16);
  74        } else {
  75                return s;
  76        }
  77}
  78
  79static int stringcomp(char *s, char *t, int op)
  80{
  81        int p;
  82        char *l, *r;
  83
  84        l = evalstr(s);
  85        r = evalstr(t);
  86
  87        p = strcmp(l, r);
  88        switch (op) {
  89        case EQ: return (p == 0);
  90        case NE: return (p != 0);
  91        case LT: return (p < 0);
  92        case GT: return (p > 0);
  93        case LE: return (p <= 0);
  94        case GE: return (p >= 0);
  95        }
  96        return (0);
  97}
  98
  99static int arithcomp (char *s, char *t, int op, int w)
 100{
 101        long l, r;
 102
 103        l = evalexp (s, w);
 104        r = evalexp (t, w);
 105
 106        switch (op) {
 107        case EQ: return (l == r);
 108        case NE: return (l != r);
 109        case LT: return (l < r);
 110        case GT: return (l > r);
 111        case LE: return (l <= r);
 112        case GE: return (l >= r);
 113        }
 114        return (0);
 115}
 116
 117static int binary_test(char *op, char *arg1, char *arg2, int w)
 118{
 119        int len, i;
 120        const op_tbl_t *optp;
 121
 122        len = strlen(op);
 123
 124        for (optp = (op_tbl_t *)&op_table, i = 0;
 125             i < ARRAY_SIZE(op_table);
 126             optp++, i++) {
 127
 128                if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
 129                        if (w == 0) {
 130                                return (stringcomp(arg1, arg2, optp->opcode));
 131                        } else {
 132                                return (arithcomp (arg1, arg2, optp->opcode, w));
 133                        }
 134                }
 135        }
 136
 137        printf("Unknown operator '%s'\n", op);
 138        return 0;       /* op code not found */
 139}
 140
 141/* command line interface to the shell test */
 142static int do_itest(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 143{
 144        int     value, w;
 145
 146        /* Validate arguments */
 147        if ((argc != 4))
 148                return CMD_RET_USAGE;
 149
 150        /* Check for a data width specification.
 151         * Defaults to long (4) if no specification.
 152         * Uses -2 as 'width' for .s (string) so as not to upset existing code
 153         */
 154        switch (w = cmd_get_data_size(argv[0], 4)) {
 155        case 1:
 156        case 2:
 157        case 4:
 158                value = binary_test (argv[2], argv[1], argv[3], w);
 159                break;
 160        case -2:
 161                value = binary_test (argv[2], argv[1], argv[3], 0);
 162                break;
 163        case -1:
 164        default:
 165                puts("Invalid data width specifier\n");
 166                value = 0;
 167                break;
 168        }
 169
 170        return !value;
 171}
 172
 173U_BOOT_CMD(
 174        itest, 4, 0, do_itest,
 175        "return true/false on integer compare",
 176        "[.b, .w, .l, .s] [*]value1 <op> [*]value2"
 177);
 178